67th Field Conference of PA Geologists
||These are three photos from Antelope Island State Park, in the Great Salt Lake in Utah. The island preserves several intervals of geologic time in its rocks, from the Precambrian to the Holocene. The top photo, facing southwest, shows a typical outcrop of the Precambrian Farmington Canyon Complex of schist, and the moon can be seen in the sky. The middle photo, shows a large boulder of the Cambrian Mineral Fork Formation, which is a lithified glacial till, or tillite, along the Elephant Head Trail. The third photo, facing southeast from the saddle between the main island and Elephant Head, shows the prominent Provo Terrace, one of at least four major terraces formed by Pleistocene Lake Bonneville. The higher Bonneville Terrace is less easy to discern but it is visible too. All photos taken May 4, 2002.|
|This photo shows an outcrop of a Tertiary Conglomerate, facing west, along FR048 in Juab County, Utah. Photo taken May 5, 2002.|
||These are photos from Capitol Reef National Park, in south-central Utah. All photos taken May 6 or 7, 2002.
The first photo, facing northeast, shows a famous landmark known as the Castle, and three Triassic formations are visible. The lowermost, reddish sandstone and shale is the Moenkopi Formation. It is overlain by greyish shale beds of the Chinle Formation. The vertically-jointed massive sandstone forming the Castle itself is the Wingate Sandstone.
The second photo, facing north, shows the same stratigraphy, but also present is the Shinarump Conglomerate Member of the Chinle Formation, which can be seen as a thin bed of tan above the reddish Moenkopi. This bed pinches out to the left.
The third photo shows preserved rain marks in the Moenkopi Formation.
The fourth photo shows criscrossing gypsum veins in the Moenkopi Formation.
The fifth photo, facing north, is a photomosaic of the Waterpocket Fold, a 100-mile-long monocline dipping to the east, preserved entirely within the park. It was taken from the top of a sandstone butte of the Jurassic Morrison Formation. The golden buttes seen in the distance in the upper right are part of Capitol Gorge.
||These are photos from Goblin Valley State Park, in Emery County, Utah. The first photo, facing north, shows a dust storm outside the park on Rt. 24 and some buttes of the Jurassic Entrada Sandstone. The second photo and third photo, facing northeast and southeast, respectively, show two views of the main goblin field as seen from the visitor pavillion. The goblins form in the Entrada Sandstone. The fourth photo shows Danielle Foye standing on one of the goblins. All photos taken May 7, 2002.|
||These are photos from the Needles District of Canyonlands National Park, in southeast Utah. The Needles District is to the east of the Colorado River within the park. The first photo shows The Needles themselves, facing southwest from Big Spring Canyon Trail. The second photo, facing northwest from Rt. 211, shows the Sixshooter Buttes. All photos taken May 8, 2002.|
These are photos from the Island in the Sky District of Canyonlands National Park, in southeast Utah. This District lies between the Colorado and Green Rivers, north of the confluence. All photos taken May 9 or 10, 2002.
The first photo, facing west from Island in the Sky, shows the Candlestick Towers of the Triassic Wingate Sandstone, as well as the White Rim Sandstone just above the Green River in the background.
The rest of the images are from a hike around and up into the center of Upheaval Dome, an eroded impact crater within the Island in the Sky District. The second photo shows some clastic dikes in the Chinle Formation along the trail on the western side of the dome. The third photo, taken from the Syncline Campsite facing south, shows a syncline in the Wingate, Kayenta, and Navajo Formations. The syncline is mappable in a ring around the dome. I hiked up into the center of the dome along Upheaval Canyon Trail (which follows a dry wash) in the morning of May 10, and took the rest of the pictures shown here. The fourth photo shows a fault in the wall of the canyon, in the Chinle Formation. It is actually one side of a graben, but the other fault is not well exposed. The next photo shows a tight fold in the bedding in the Chinle Formation. Sights like this become more common towards the center of the dome. The next photo shows a large, vuggy boulder along the trail that hikers have stacked small stones into its vugs. Piles of stones are frequently used to mark trails in Canyonlands and other parks in the southwest. The next several photos are from the central part of the dome, and show some of the steeply dipping beds of the Chinle, Moenkopi, and Cutler Formations. The last photo shows abundant sand waves of various sizes and directions within the Moenkopi Formation, also near the center of the dome.
||These are photos from Medford Quarry, Carroll County, Maryland, which I visited on June 29, 2002. The calcite in this quarry contains Niobium, which gives some of the crystals a purplish color, such as that of mq3. Other rocks collected at the quarry include mq1 and mq2.|
||These are photos from the 67th Annual Field Conference of Pennsylvania Geologists, which was entitled From Tunkhannock to Starrucca: Bluestone, Glacial Lakes, and Great Bridges in the "Endless Mountains" of Northeastern Pennsylvania. It was held on October 3 to 5, 2002.
The first day was for optional trips of smaller groups. I chose to go with Dr. Duane Braun of Bloomsburg University to check out the geology of Glacial Lake Great Bend. The first photo is from Stop 4 of his trip, at a sand and gravel quarry. This deposit was formed under the lake while it was at its highest level - about 1200' above sea level.
The second photo is from Stop 1 of the second day (the first day of the main field trip) at the State Aggregates Clifford Quarry. It shows a cluster of tree fossils in a single boulder of the Devonian Catskill Formation. A cluster like this is sometimes referred to as phlassenhacksel, which means "log jam".
The third photo is from Stop 2. It shows a sequence of deposits that Starrucca Creek has cut down through in the Holocene. There is lodgement till at the bottom, overlain by glacial outwash, overlain by varved clays (lake deposits), and capped by Holocene alluvium. And the top three layers are cut by a fault. The fourth photo is also from Stop 2, which also included a quarry in the Catskill Formation. It shows Skolithos trace fossils (viewed either from the top or the bottom) in a boulder from the quarry.
The last photo is from Stop 4, at the Endless Mountain Stone Company's Coleman Quarry. This quarry mines and processes slabs of the Catskill Formation for bluestone. The photo shows a cut slab of a thick bed with large mudclasts, or rip-up clasts, as well as prominent crossbedding. One can tell from this crossbedding that the bed is upside-down in this photo. I collected this sample from the quarry, already cut.